Download Electricity Review - Maine South High School

Electricity Review
Electrostatics and Circuits
If you bring a positively charged
strip near a foil ball and the ball
is attracted to the strip. You know
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The foil ball is positive
The foil ball is negative
The foil ball is neutral
The foil ball is either negative or neutral
The foil ball is either positive or neutral
The correct answer is …..
The foil ball is either negative or neutral
The outlets in your house are
connected in ______
• Series
• Parallel
• The answer is ….
• Series …
• Just kidding! Parallel is correct!
Most Christmas tree lights are
connected in ______
• Series
• Parallel
• The answer is ….
• Series. Really, it is!
If you bring a charged strip near
an electroscope that is neutral,
the leaves
• Spread and have the same charge as the
charged strip
• Spread and have the opposite charge as the
charged strip
• come together and have the same charge as
the charged strip
• come together and have the opposite charge
as the charged strip
The correct answers is...
• Spread and have the same charge as the
charged strip
Opposite charges
• Attract
• Repel
• Fight in a cage match
The correct answers is...
• Attract!
What is the current traveling
through a 20 Ohm resistor with
120V across it?
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The correct answer is….
I = V/R
I = 120 V/20 Ω
I = 6A
When an atom has the same
number of protons as electrons, it
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Is negative
Is positive
Is neutral
Is all good!
• The correct answer is…
• It is neutral.
Voltage across resistors in
parallel is
• The same and equal to the voltage across
the source
• Varies depending on the resistance of the
resistor
• Adds up to the voltage of the source.
• The correct answer is….
• The same and equal to the voltage across
the source
What is the current traveling
through a 5 Ohm resistor and 10
Ohm resistor in series with a 30
Volt source?
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0.5 A
1A
2A
3A
6A
The correct answer is….
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Total resistance is 15 Ω (5Ω+10Ω)
I = V/R
I = 30 V/15Ω
I = 2A
As I add more resistors in
parallel, what happens to the
total current in the circuit?
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It increases
It decreases
It stays the same
It makes funny typing noises!
The correct answer is….
It increases.
As I add more resistors in series,
what happens to the total current
in the circuit?
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It increases
It decreases
It stays the same
It stays quiet!
The correct answer is….
It decreases.
When you charge a clear plastic
strip by rubbing it against a paper
towel, what is the name of this
method of charging?
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Friction
Conduction
Induction
Conjunction
The correct answer is….
Friction!
As I add more resistors in
parallel, what happens to the
total resistance in the circuit?
• It increases
• It decreases
• It stays the same
• The correct answer is…
• It decreases!
When an atom has more protons
than electrons, it
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Is negative
Is positive
Is neutral
Is out of control!
The answer is...
• It is positive!
As you add more resistors in
series, what happens to the total
resistance in the circuit?
• It increases
• It decreases
• It stays the same
• The answer is…
• It increases!
Two 2 Ohm resistors are in
parallel with a 10 Volt source,
what is voltage across one of 2
Ohm resistor
• The answer is ….
• 10 Volts
A 2 Ohm resistor has 10 Volts of
potential difference across it, what
is the current in 2 Ohm resistor?
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0.2 A
1A
2A
5A
10 A
The correct answer is...
• I = V/R
• I = 10 V/2Ω
• I = 5A
If you add another 2Ω resistor in
series with the 2Ω in the last
problem, what will be the total
current?
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0.2 A
2.5 A
2A
4A
10 A
The correct answer is….
2.5A!
If you add another 2Ω resistor in
parallel with the 2Ω in the last
problem, what will be the total
current?
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0.2 A
1A
2A
4A
10 A
The correct answer is….
10 A!
Same charges
• Attract
• Repel
• Wrestle in a royal rumble
• The answer is…
• repel! Really, it is!
When a negatively charged strip
touches an electroscope and
charges it negatively, this is an
example of what charging
method?
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Friction
Conduction
Induction
The answer is…
Friction ….
Get real! It is conduction!
If you bring a positively charged
strip near a foil ball and the ball is
repelled by the strip. You know
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The foil ball is positive
The foil ball is negative
The foil ball is neutral
The foil ball is either negative or neutral
The foil ball is either positive or neutral
The correct answer is …..
The foil ball is positive
When you bring a charged object near a
neutral object (without touching it) and
cause the charge to move within the
object, this is what method of charging?
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Friction
Conduction
Induction
The answer is…
Induction!
When an atom has more electrons
than protons, it is
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Negative
Positive
Neutral
Cool, dude!
• The answer is...
• it is both negative and cool, dude!
Good Luck on the test, tomorrow!
Here are some suggestions about how to study:
• Look over the labs, especially concentrate
on the questions and their answers.
• Skim through the reading assignments and
the look over the questions and their
answers.
• Look over the worksheets and try solving
some of the problems again without looking
at your answers.